Tire-building apparatus



Feb. 25, 1930. c, MAYNARD 1,748,300

MARKING DEVICE Filed June 1928 h INVENTOR. l f mamas 2m JYAIMPD- BY Q) Z6 ATTORNEY.

Patented Feb. 25, 1930 UNITED STATES PATENT OFFICE CHARLES EDGAR MAYNARD, OF NORTHAMPTON, MASSACHUSETTS, ASSIGNOR TO THE FISK RUBBER COMPANY, OF GHICOPEE FALLS, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS MARKING DEVICE Application filed June 2, 1928. Serial No. 282,322.-

My invention relates to apparatus for marking continuous sheets of material and more particularly to apparatus for marking continuous sheets of rubberized cord or woven fabric such as is used in the manufacture of pneumatic tires, and has for its object to provide a marking device which will imprint on both sides of rubberized material a series of markings without damaging the material and without the use of any marking agent. Another object is to provide a marking device which may supply any desired number of identifying markings in such a way as to permit a rapid change from one identifying marking to another. Other objects will be apparent from the specification and claims;

The marking of rubberized cord or fabric stock for use in pneumatic tires has, up to the present, as far as applicant is aware, been a problem which has never been satisfactorily solved. The large production of the many\ grades of pneumatic tires now manufactured necessarily demands many grades of rubberized cord or fabric stock used in their manufacture. As it is very difficult to distinguish by appearance between the different grades of rubberized stock, it is advantageous to use some identifying means as it is calendered. Marking crayon was tried but found unsatisfactory as it introduces foreign matter into the finished tire, thus weakening its construction. Rubber cement has also been used and found objectionable due to the maintenance Fig. 5 is a view of a piece of material showing the identifying marks on both sides.

As indicated on the drawings, 10 represents a frame on which are mounted bearings 11 supporting a shaft 12 (Fig. 1). Keyed to the shaft 12 are two wheels 13 (Fig. 2) each having eight equally spaced radial guideways 14 and bolted on side plates 15. Around the periphery of wheel 13 are bolted indexing blocks 16. Confined in the radial guideways 14 by ball bearings 17 are marking rollers 18 which bear spacing collars 19 and marking dies 20 (Figs. 2 and 3) the latter being bolted to the rolls 18 by bolts 21 at different angles as shown in Fig. 1. For clearness only two such marking rollers are shown in the drawingsbut it will be obvious that six more,

each with different marking dies 20, may be added by simply removing the correct indexing blocks 16, inserting the marking rollers and rebolting the indexing blocks.

Positioned below the marking rollers 18 and in the same vertical plane as shaft 12 is a roller 22 supported by bearings 23 to the frame 10 and over which travels the rubberized stock 24 from calender rolls 25. Linked to the bearings 11 by links 26 is a locking bar 27 (Fig. 4) kept in the correct Vertical alignment by guiding slots in the extensions 28 of bearings 11. Vhen'the locking bar 27 is in the full line position shown in Fig. 4 it engages slots 29 in the uppermost indexing block 16 on each wheel 13 to position the diametrically opposite marking roller 18 in operating relation with the roller 22 as shown in Fig. 2. Any of the other marking rollers may be brought to this position by raising the locking bar 27 to the dotted line position shown in Fig. 4 and rotating the wheels 13 to the correct indexing blocks 16.

As is shown in Fig. 2 the spacing collars 19 on the marking roller 18 rest on roll 22 and the ball bearing 17 engages the guideways 14 to prevent any horizontal movement but to allow a free vertical movement of the marking roller 18 thus giving the latter a floating roll action and, as the roll 22 is rotated by the stock 24, the spacin collars 19 will rotate the marking roller in t e opposite direction (see Fig. 3).

The faces of the marking dies 20 are kept at a constant separation from the roll 22 by the spacing collars 19 (see Fig. 3) but as the separation is less than the thickness of the rubberized stock 24 the marking dies 20 produce an impression 30 on each side of the stock 24 as shown in Figs. 3 and 4. The weight of the combined markin roller 18, spacing collar 19, etc., is enoug to overcome the resistance of the warm rubber so that the spacing collar 19 engages the roll 22 at all times.

The separation between the faces-of the marking dies 20 and the roll 22 is governed by the dimensions of the spacing collars 19 and has been found from experiment to be critical in so much as too little separation may permit the dies to cut the imbedded cords 31 and too great a separation will not produce a satisfactory marking. Following is a typical example with a roll weighing approximately 120 pounds:

Average thickness of stock .050" Compression needed for imprinting .033"

Separation between marking dies and roll .017"

The warm rubber is in a condition to flow sufliciently easily to be displaced by,the pressure of the die and this displacement takes ace, as shown in Fig. 3, on both sides of the material if both sides are coated. Preferabl the spacing of the dies from roll 22 is suc that, assuming the material to be a cord fabric, a relatively thin film of rubber is left over the cords at the points of impression with the result that the lines of the cords show sufiiciently to give the marking a characteristic lined appearance easily distinguishable from the relativel smooth surrounding surface. This line efl'ect is indicated in Fig. 5. When the coated material is a woven fabric as distinguished from cord fabric the markin shows the characteristic weave of the material. It will be understood that no rubber is removed and that the marking [in no way harms the material.

aving thus described my invention, I claim:

1. A device for marking rubber coated I material comprising a supporting roll adapted to support a moving sheet of rubber coated material and to be rotated by the latter, two su porting and indexing wheels, a plurality o radial guideways in the wheels, rotatable die supporting members positioned in the radial uideways, spacing rollers attached to the ie supporting members, index blocks attached to the periphery of the sup porting and indexing wheels, a locking bar positioned to engage said index blocks to permit any one of the die supporting members to be held in such a relation with the supporting roll that the spacing collars engage the supporting roll to rotate the die supporting member and to maintain a predetermined spacing between the dies and the supporting roll to form a series of identifying marks on each side of the moving sheet of rubber coated material.

2. A device for marking rubber coated material comprising a supporting roll adapted to support a moving sheet of rubber coated material and to be rotated by the latter, two supporting and indexing wheels, rotatable die supportin members journaled in said wheels adjacent t eir peripheries, spacing rollers attached to the die supporting members, means to lock said wheels in position to hold a selected die supporting member in such relation with the supporting roll that the spacing collars engage the supporting roll to rotate the selected die supporting member and to maintain a predetermined spacing between the dies and the supporting roll to form a series of identifying marks on each side of the moving sheet of rubber coated material. 1

CHARLES EDGAR MAYNARD. 

